Field of the Invention
The present invention relates to a plugged honeycomb structure, and a manufacturing method of the plugged honeycomb structure. More particularly, the present invention relates to a plugged honeycomb structure which is for use in a diesel particulate removing filter (DPF) or the like and is capable of trapping and removing particulates constituted of particulate matter, and also relates to a manufacturing method of the plugged honeycomb structure.
Description of the Related Art
Heretofore, honeycomb structures made of ceramics have been applied to various uses in a car exhaust gas purifying catalyst carrier, a diesel particulate removing filter, a heat reservoir for a burning device and the like. For example, the diesel particulate removing filter is used to trap particulate matter in an exhaust gas emitted from a diesel engine, and in the filter, a honeycomb structure (a plugged honeycomb structure) is usually used in which one end of each predetermined cell is plugged by a plugging member and the other end of each of the residual cells is plugged by the plugging member.
In the above plugged honeycomb structure, a ceramic material such as a cordierite component or a silicon carbide component is used. For the purpose of achieving decrease of pressure loss of the plugged honeycomb structure, increasing of a porosity of a partition wall constituting the plugged honeycomb structure is advanced (see, e.g., Patent Documents 1 and 2).
When the increasing of the porosity of the partition wall is performed, a mechanical strength of the plugged honeycomb structure necessarily decreases. As a result, especially a partition wall portion of each cell end is easy to crack. To eliminate such a problem, there has been suggested development of a plugged honeycomb structure whose end portions are hard to crack and which is excellent in durability (see, e.g., Patent Document 3).
[Patent Document 1] JP-A-2003-269132
[Patent Document 2] JP-A-2011-189252
[Patent Document 3] JP-A-2004-154692